Arthroscopic Treatment of Posterior Shoulder Instability

BACKGROUND: Posterior shoulder instability is a relatively rare condition and a surgical challenge. Arthroscopic techniques have allowed for a potential improvement as well as diagnosis and management of this condition. PURPOSE: To evaluate the outcomes of arthroscopic posterior shoulder stabilization and to evaluate preoperative and intraoperative variables as predictors of success. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Thirty-three consecutive patients with a mean age of 25 years (range, 19-34 years) who underwent posterior arthroscopic shoulder stabilization with suture anchors (mean, 3 anchors) or suture capsulolabral plication (mean, 5.3 stitches) or both were reviewed at a mean follow-up of 39.1 months (range, 22-60 months). Shoulder outcomes rating scores were determined using the American Shoulder and Elbow Surgeons Rating Scale, the Western Ontario Shoulder Instability Index, the Subjective Patient Shoulder Evaluation, and the Single Assessment Numeric Evaluation. RESULTS: There were 7 failures: 4 for recurrent instability and 3 for symptoms of pain. Overall, outcomes scores demonstrated mean values of the American Shoulder and Elbow Surgeons Rating Scale of 94.6, Subjective Patient Shoulder Evaluation of 20.0, Western Ontario Shoulder Instability Index of 389.4 (81.5% of normal), and Single Assessment Numeric Evaluation of 87.5. Patients with voluntary instability demonstrated worse outcomes (P = .025), and those with prior surgery of the shoulder also did worse (P = .02). CONCLUSION: Arthroscopic treatment of posterior shoulder instability is an effective means to improve symptoms associated with recurrent posterior subluxation of the shoulder. It can provide predictable success in the setting of unidirectional, nonvoluntary posterior instability without prior surgery.